Device and method for suturing intracardiac defects

ABSTRACT

In accordance with the present invention there is provided a suturing device. The suturing device includes a length of suture that will be delivered to the site of the PFO and placed through the tissue adjacent the opening to close the PFO. As described in greater detail below, the suture is advanced through the tissue surrounding the opening by a pair of needles that penetrate the tissue adjacent to the opening. A knot is then loosely tied with the length of suture and advanced to the site of the PFO. The tails of the suture extending from the knot are then cut and removed. It is also contemplated that a pre-formed or pre-tied knot may be disposed on the device, wherein after deployment of the suture through the tissue adjacent to the PFO and removal of the device a loop of suture having a pre-tied knot will remain, wherein the pre-tied knot may then be tightened to close the PFO. Further still it is contemplated that other means may be utilized to retain the sutures. For example, it is contemplated that a suture clip or other clip like device may be utilized to retain the suture in a position such that the PFO is closed.

PRIORITY CLAIM

The present application claims priority to the following U.S.Provisional Patent applications having Ser. Nos. 60/506,536 and60/540,811 filed on Sep. 26, 2003 and Jan. 30, 2004 the entireties ofwhich are herein incorporated by reference.

RELATED APPLICATIONS

This application is related to the following U.S. Patent applications:

-   -   Application Ser. No. 10/660,288, filed Sep. 11, 2003;    -   Application Ser. No. 10/652,182, filed Aug. 29,2003;    -   Application Ser. No. 10/357,984, filed Feb. 4, 2003;    -   Application Ser. No. 10/152,272, filed May 20, 2002;    -   Application Ser. No. 09/651,344, filed Aug. 29, 2000; and        application Ser. No. 09/262,402, filed on Mar. 4, 1999, now U.S.        Pat. No. 6,136,010.

The disclosures of application Ser. No. 10/660,288, filed Sep. 11, 2003;application Ser. No. 10/652,182, filed Aug. 29, 2003; application Ser.Nos. 09/651,344, 10/152,272, and 10/357,984, as well as U.S. Pat. No.6,136,010 are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The present invention relates generally to devices and methods forsuturing intracardiac defects, and more particularly, to transcatheterdevices and methods for suturing of an intracardiac defect such as apatent foramen ovale.

BACKGROUND OF THE INVENTION

The foraman ovale is an opening between the two aria of the fetal heat.It usually closes shortly after birth as a result of hemodynamic changesrelated to respiration. If it remains open, or “patent,” the defect canbe repaired surgically. Taber's Cyclopedic Medical Dictionary, 18^(th)Ed., 1997, p. 747.

As association has been found between PFO and cryptogenic stroke inpatients younger than sixty five (65) years old that suggests that PFOallowing paradoxic embolus may be responsible for stroke when othercauses cannot be identified. Id. It has been theorized that closing thepatent foramen ovale may be beneficial in reducing incidence of strokeor transient ischemic attacks (TIA) in patients with PFO.

Devices and methods for transcatheter-based repair of atrial septaldefects (ASD) and patent foramina ovalia (PFO) have been developed. Thedesign of such transcatheter devices is largely driven by the structureof the intracardiac and intravascular anatomy. ASDs are relativelysimpler lesions, being generally circular or oval shaped defects withina relatively thin spetum. Marchall A. C., Lock J. E., Structural andCompliant Anatomy of the Patent Foramen Ovale in Patients UndergoingTranscatheter Closure, Am Heart J 2000 August; 140(2);303-7. Theanatomical structural features of PFO's, however, are more complex. Id.“[T]tle PFO involves two components, septum primum and septum secundum.Septum secundum is thicker than septum primum and exhibits limitedmobility and compliance. The failure of these two structures to fusecreates a tunnel-like opening, the PFO. The extent to which these twocomponents of the atrial septum overlap determines the length of thistunnel. The distance of the nonfusion between the septa, when viewedfrom the left atrial surface, determines its breadth. This later measureultimately limits the potential size of the PFO. These uniquecharacteristics, which distinguish the PFO from the ASD, should beconsidered in the design of a device targeted specifically at PFOs.” Id.

“Initial attempts to accommodate the unique anatomy of the PFO yieldeddevices composed of a pair of offset discs set apart by a relativelylong central section. This section theoretically allowed for the lengthand angulation of the PFO tunnel. The long central section, however,increased bulkiness of the device. Furthermore, we subsequently observedthat the central body of the double disc device actually displaced therelatively compliant septum primum, thus shortening the length of thePFO tunnel. After device placement, the long central pin unnecessarilyincreased the device profile in the heart, thus potentially preventingcomplete endothelialization. Any relatively rigid device that failed toanticipate changes in the topography of the atrial septum could havesimilar drawbacks. Thus placement of a device designed for the staticrather than the compliant anatomy of the atrial septum could fail tomeet the needs of patients with PFO and a history of cryptogenicstroke.” Id.

“Transcatheter closure devices have been used to treat lesions asdiverse as ASD, ventricular septal defect, and PFO despite the fact thatmost of these devices were originally designed to close the simple ASD.Ventricular septal defects clearly present challenging substrates forclosure devices, often with irregularly configured defect in a thick,muscular septum. Perhaps less well-recognized is the fact that the PFOalso poses a unique challenge based on anatomic characteristics ofseptum secundum, septum primum, and the dynamic relation between thetwo.” Id.

Atrial septal defects have been initially corrected by open heartsurgery which required the surgeon to open the chest of a patient andbypass the heart temporarily (eg by means of a heat-lung machine andmoderate hypothermia). The surgeon would then physically cut into theheart and suture small defects closed. In the case of larger defects, apatch of biologically compatible material would be sewn onto the septumto cover the defect.

In order to avoid the morbidity, mortality and long recovery timesassociated with open heart surgery, a variety of transcatheter closuretechniques have been invented. In such techniques an occluding device isdelivered to the defect site. Once the occluding device is in positionit is deployed, wherein many of these devices are configured to beretained within the defect through the use of tension forces, springforce, clips or similar technology. Examples of such occluding devicescan be seen in U.S. Pat. Nos. 3,874,388; 4,917,089; 5,725,552; and5,334,217, wherein these devices are configured to be delivered to thedefect in an unexpanded state and then be deployed or opened to seal thedefect.

The prior art devices of the above-referenced patents each have theirown shortcomings. For example, many of the devices require complexloading devices for delivery of the device to the defect. Additionally,many of the devices require time consuming positioning and deploymentprocedures which have a high margin for error. Still further, many ofthe devices require extensive remote manipulation to anchor or deploythe device, this not only increases the amount of time required todeploy the device but also increases the likelihood of errors duringdeployment.

In addition to those shortcomings mentioned above, another shortcomingis that many of the devices have a geometry which tends to prevent thedevice from remaining flat against, or within the defect once deployed.Lastly, each of the devices in their expanded and deployed conditionleave a large surface area of material within the patient's body,wherein this large area of material may lead to the formation ofthromobosis or cause a reaction in the patient's body.

Additionally, many devices on the market are configured such that thepatients anatomy must be adjusted to fit the geometry of the device. Forexample, if the PFO consists of a puncture or small opening, a sizingballoon is passed through the opening to conform the opening to the sizeof the device, many times this involved tearing of the tissue to form alarger opening to receive the device.

Therefore there is a need for improved devices that can be easilydeployed within a patient's anatomy without having to alter thepatient's anatomy and while leaving the smallest amount of foreignmaterial exposed to the patient's blood stream.

There is also a need for improved devices which when in a deployed stateare physically anchored to the patient's anatomy thereby preventing thedevice from possibly migrating within the patient's anatomy over timeand causing other complications.

These and other objects, advantages, and features of the invention willbecome apparent to those persons skilled in the art upon reading thedetails of the methods and systems of the present invention that aremore fully described below.

SUMMARY OF THE INVENTION

In accordance with the present invention there is provided devices andmethods for suturing intracardiac defects. The devices according to thepresent invention include a handle portion, an elongate shaft, and afoot housing having a deployable foot and at least two needles and alength of suture. According to the methods of the present invention thedevice is introduced to a patient's vasculature, wherein the foothousing of the device is passed through an intracardiac defect such as apatent foramen ovale, the foot is deployed and the device is pulled backagainst the septum primum and secundum. After placing the foot againstthe primum and secundum, at least one needle and more preferably twoneedles are deployed from the elongated shaft and received by the foot,thereby placing a suture loop between the primum and secundum. Thesuture loop may be terminated by tying a knot or using a suture-lockingdevice, thereby closing the intracardiac defect.

In accordance with the present invention there is provided a suturingdevice having a housing having a foot actuation handle and a needleactuation handle, the housing having a proximal end and a distal end; aflexible shaft extending from the distal end of the housing, theflexible shaft having proximal end and a distal end; a foot housingextending from the distal end of the shaft, the guide carrying apivotable foot, the foot being operative connected to a foot actuationwire, the foot actuation wire being connected to the foot actuationhandle; at least one needle extending from the needle actuation handleand through the shaft; a length of suture having two ends, the length ofsuture positioned on the device; and a distal sheath extending from thefoot housing, the distal sheath defining a guidewire lumen.

In accordance with the present invention there is provided a suturingdevice comprising: a housing; a elongate tubular member having aproximal portion and a distal portion; an elongate foot movably mountedwithin a foot housing; a foot actuation handle operatively coupled tothe elongate foot, wherein movement of the foot actuation handle causesthe foot to pivot from a low profile configuration substantially alignedwith the foot housing to a deployed configuration extending at an anglefrom the foot housing; a pair of needles advanceable from the proximalportion of the shaft to the deployed foot, at least one needle having adistal end carrying a detachable tip, the detachable tip connected to afirst end of a length of suture, the suture having a second end and abight between the first and second ends, the bight being prearranged onthe outer surface of the device to define a pre-tied knot or a sutureloop, wherein the first end passes through the bight.

In accordance with the present invention there is provided a suturingdevice, comprising: an elongate housing having a proximal end and adistal end; a first foot mounted to move relative to said elongate body,said first foot including a needle receiving portion and beingactuatable between a first and second position, said needle receivingportion being substantially within said housing in said first positionand said needle receiving portion disposed outwardly away from saidhousing in said second position; a first needle having a distal end,said needle mounted to move longitudinally along at least a portion ofthe extension of said elongate body in a proximal to distal directionand into said needle receiving portion when said arm is in said secondposition; and a length of suture having a first end and a second end, atleast one of the ends including a toggle disposed thereon.

In accordance with the present invention there is provided a method forsuturing a patent foramen ovale, the method including the followingsteps: (a) providing a suturing device including a housing having a footactuation handle and a needle actuation handle, a flexible shaftextending from the distal end of the housing, a foot housing extendingfrom the distal end of the shaft, the guide carrying a pivotable foot,the foot being operative connected to a foot actuation wire, the footactuation wire being connected to the foot actuation handle; at leastone needle extending from the needle actuation handle and through theshaft; a length of suture, and a distal sheath extending from the guide,the distal sheath defining a guidewire lumen. (b) Advancing the suturingdevice through the inferior vena cava, right atrium, and patent foramenovale such that the foot is positioned in the left atrium. (c) Deployingthe foot to a deployed position; advancing the at least one needlethrough tissue and further into a needle receptacle, and (d) advancingat least one end of the length of suture through the tissue to suturethe PFO.

DETAILED DESCRIPTION OF THE DRAWINGS

Preferred embodiment(s) of the present invention are described hereinwith reference to the drawings wherein like numerals have been utilizedto denote similar components.

FIG. 1. is a plan view of a suturing device in accordance with thepresent invention.

FIG. 2a . is a cross-sectional view of the shaft of the suturing devicetaken about line 2-2 of FIG. 1.

FIG. 2b . is a plan view of an exemplary embodiment of a reinforcementlayer in accordance with the present invention.

FIG. 3. is a cross-sectional view of the shaft of the suturing device ofthe present invention taken about line 3-3 of FIG. 1.

FIG. 4. is a plan view of the needle actuation assembly in accordancewith the suturing device of the present invention.

FIG. 5. is a cross-sectional view of the articulating foot of thesuturing device in accordance with the present invention.

FIG. 6a . is a plan view of one embodiment of a suture that may beutilized in accordance with the device and methods according to thepresent invention.

FIG. 6b . is a plan view of an alternative embodiment of a suture andsuture-locking device that may be utilized in accordance with the deviceand methods according to the present invention.

FIG. 6c . is a plan view of an exemplary embodiment of a sealing memberin accordance with the present invention.

FIG. 6d . is a plan view of an alternative embodiment of a sealingmember in accordance with the present invention.

FIG. 7. is a partial view of an alternative embodiment of the deviceaccording to the present invention illustrating a pre-formed suturebight disposed about a needle and adjacent the foot of the device.

FIG. 8. is a partial plan view of an alternative embodiment of the footand foot housing of the suturing device in accordance with the presentinvention.

FIG. 9. is a cross-sectional view of a distal tip of an alternativeembodiment of a needle and suture assembly according to the presentinvention.

FIG. 10. is an exemplary embodiment of a suture path formed with thedevice according to FIGS. 8 and 9.

FIG. 11. is a plan view of a heart illustrating a PFO wherein thesuturing device in accordance with the present invention is showndisposed through the PFO.

FIG. 12. is a plan view of a heart illustrating a PFO wherein thesuturing device in accordance with the present invention is showndisposed through the PFO, wherein the articulating foot is shown in adeployed position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In accordance with the present invention there is provided a device andmethods for closing intracardiac defects. The device according to thepresent invention include a handle portion, a flexible elongated memberextending from the handle portion at one end and connected to a foothousing at the other end, a deployable foot disposed within the foothousing and a flexible distal tip. At least one needle and morepreferably two needles are disposed within the flexible elongatedmember. The suturing device is configured to dispose a length of sutureacross the site of a PFO, wherein the suture is placed through thetissue adjacent the opening to close the opening. As described in moredetail below, the suture is advanced through the tissue by a pair ofneedles that penetrate the tissue adjacent the opening, connect with theends of the suture, and move the suture through the penetrations in thetissue to span the opening. A knot is then loosely tied with the lengthof suture and advanced to the site of the PFO. The tails of the sutureextending from the knot are then cut and removed. It is furthercontemplated that a bight of suture may be pre-arranged on the body ofthe device, wherein after the suture has been passed through the tissueand across the opening, the bight of suture is detached and forms a knotor a suture loop, wherein the knot or suture loop may be advanced toclose the opening. Still further it is contemplated that asuture-locking device may be utilized in the place of a knot to effect aclosure of the opening. Examples of a suitable suture-locking device canbe seen in U.S. provisional patent application having Ser. No.60/502,295 filed Mar. 15, 2004 and U.S. the entirety of which is herebyincorporated by reference.

In accordance with alternative embodiments of the device in accordancewith the present invention, the device may be utilized to dispose othertypes of closure devices across the PFO. For example, in accordance withone alternative embodiment, a suture having a self-tightening featuremay be disposed across the opening, wherein after being placed acrossthe opening the opening may be closed by applying a force to one end ofthe suture. In another alternative embodiment, the suture ends may havea pre-scored line or feature that is configured to sever the sutureabove a knot in response to a predetermined force being applied to theend of the suture. These and other alternative embodiments will bedescribed in greater detail below with reference to the appropriatedrawing figure.

The suturing device according to the present invention preferablyincludes a housing at its proximal end that functions as the main handleor control portion of the device. The housing has associated with it amovable or pivotable foot handle and a movable or slidable needleactuation handle. A flexible shaft extends from the distal end of thehousing. A foot housing is attached to the distal end of the flexibleshaft. The foot housing carries a pivotable foot. A distal sheath isattached to the distal end of the foot housing, wherein the flexibleshaft further includes at least one suture and one needle disposedtherein and more preferably at least two needles. The foot furtherincludes a flexible filament, one end being configured to receive afirst needle tip and the second configured to be received by the secondneedle as will be described in greater detail below with reference tothe appended figures.

As shown in FIG. 1, the suturing device 10 includes a handle assemblyincluding a handle portion 20 having proximal and distal ends. A footactuation lever 30 being pivotally associated with the handle portion 20and disposed adjacent the proximal end of the handle portion 20. Aflexible shaft 50 extends from the distal end of the handle portion 20,wherein the distal end of the flexible member 50 being associated with afoot housing 60. The foot housing having a proximal end and a distalend, the proximal end being coupled to the distal end of the handleportion 20 through flexible shaft 50 and the distal end of the foothousing coupled to the distal sheath 70. The suturing device 10 furtherincluding a needle actuation handle 40, wherein the needle actuationhandle extends from the proximal end of the handle portion 20, whereinthe needle actuation handle 40 is operationally coupled to at lease oneneedle and preferably two needles disposed within the handle portion 20and the flexible shaft 50 as will be described in greater detail below.The foot actuation lever 30 is operatively coupled with a foot 65,wherein the foot 65 is disposed in a foot housing 60.

As shown in FIG. 1, the distal sheath 70 is preferably constructed of aflexible material such as Pebax. The sheath is a generally tubularmember that defines a guidewire lumen communicating with and extendingbetween a guidewire entry port 72 and a guidewire exit port 73. Thelength of the distal sheath may be about 1 inch to about 6 inches andmore preferably between about 2 and about 4 inches. The distance betweenthe guidewire entry and exit ports may be between about 1 inch to about6 inches and preferably between about 2 and about 4. The distal sheathmay be tapered in the distal direction and may have a J-tip or astraight tip at its distal end. The flexibility of the distal sheath, inone embodiment, progressively increases in the distal direction. It iscontemplated that the length of the distal sheath my be chosen such thatthe distal sheath has sufficient length to be received within thepulmonary vein to further align the device within a patient's anatomy.

As shown in FIG. 1, the proximal end of the flexible shaft 70 is coupledto the distal end of the foot housing 60. The foot housing 60 isconfigured to house a foot 65, wherein the foot 65 is configured to bepivotally attached to the foot housing 60. Foot 65 is configured to movebetween a low profile delivery configuration, in which the foot issubstantially housed and aligned along an axis of the foot housing 60(as illustrated in Figure. 1), to a deployed position, in which the footextends laterally from the shaft, upon actuation of foot actuationhandle 30 disposed on proximal housing 20 as shown in FIG. 5.

In the delivery configuration illustrated in FIG. 1, the foot 65 extendssubstantially along and within the foot housing 65. As shown the foothousing 65 may have a curved portion, the curved portion beingparticularly adjacent the foot 65 wherein the apex of the curve of thefoot housing 60 may be centered about the pivot point 61 of thearticulating foot 65. In the exemplary embodiment, foot 65 issubstantially disposed within a foot housing 60 so as to minimize thecross-section of the device adjacent the foot prior to deployment.Advantageously, prior to deployment of the foot 65, device 10 can have across-section adjacent foot 65 between about 6 and 18 Fr and morepreferably between about 8 and 12 Fr.

As described above, the foot housing 60 preferably includes a curvedportion disposed between the proximal and distal end of the foothousing, wherein the curved portion of the foot housing 60 is configuredto aid in placement of the device 10 within the patient's anatomy aswell as enhance tissue capture as will be described in greater detailbelow with regard to the methods in accordance with the presentinvention.

The proximal end of the foot housing 60 is coupled to a flexible shaft50, wherein the flexible shaft 50 is an elongate tubular shaftconstructed having a degree of flexibility sufficient to allow theflexible shaft 50 to be advanced through tortuous blood vessels,arteries and/or body cavities. The flexible shaft 50 preferably hasadequate column strength to resist buckling during deployment of thefoot 65, i.e., when tension is applied to a deployment wire 32 extendingthrough the lumen of the shaft between the foot deployment handle 30 atthe proximal end of the flexible shaft 50 and the foot 65 at the distalend of the flexible shaft 50. The inner and outer surfaces of the shaftmay be covered with a polymer sleeve or coating such as Pebax. Theflexible shaft 50 may have a length between about 10 inches and about 48inches, more preferably between about 18 and about 36 inches.

Referring now to FIG. 2a , there is shown a cross-sectional view of theflexible shaft 50 taken about line 2-2 of FIG. 1. As shown in FIG. 2a ,the flexible shaft 50 may be formed of multiple layers, each layerhaving different mechanical properties. For example, the flexible shaft50 may be constructed having inner layer 51 and outer layer 52 formed offlexible materials such as polyurethane or polyvinylchloride (PVC)wherein a middle reinforcing layer 53 is sandwiched between the twolayers. The reinforcing layer 53 is preferably disposed between theinner layer 51 and the outer layer 52. In one embodiment, thereinforcing layer 53 includes braided material. For example, thereinforcing layer 53 can be provided in the form of a braided stainlesssteel tube or sheet. Preferably, the braid includes flattened filaments,as opposed to having filaments with a round cross-section. Although ametallic braided is preferred, it is not necessary. It is also possibleto provide a woven fabric or appropriately oriented filaments, such ascarbon fibers encased in a polymeric matrix. Likewise, such reinforcingfibers could additionally or alternatively be incorporated into theinner layer 51 and/or the outer layer 52 during the manufacturingprocess. The reinforcing layer 53 need not be present through the entirelength of the flexible shaft 50. For example, it is possible forreinforcing layer 53 to be provided along the proximal portion of shaft50 only, or some greater or lesser portion.

Suitable materials of which the inner and outer layers of the flexibleshaft 50 may be constructed from include polymeric materials such asPEEK and preferably traverses substantially the entire length of theflexible shaft 50. However, any of a variety of materials can be usedfor the inner and outer layers of the flexible shaft 50. For example,flexible shaft 50 could be made from other polymers such as PTFE, PVDF,Kynar, or polyethylene of various suitable densities.

In an alternative embodiment, one or more than one layer of the flexibleshaft 50 may be constructed from a metallic material such as Nitinol orstainless steel, wherein reliefs may be formed in the wall of themetallic material to provide flexibility. As a further alternative, theflexible shaft 50 can be a composite member comprising a fabrication ofseveral different materials, such as a co-extrusion of differentpolymers, or fiber-reinforced composite material such asfiber-reinforced resin material.

Additionally as shown in FIG. 2a , the flexible shaft 50 furtherincludes at least one foot actuation wire and more preferably two footactuation wires 32, two needles 42, and a suture storage lumen 80. Thesuture storage lumen may be a separate elongated tube disposed withinthe flexible shaft 50, or the flexible shaft 50 may be constructedhaving multiple lumens integrally formed therein, where one lumen wouldbe configured as a suture storage lumen 80, another lumen may beconfigured to contain one or more of the needles or actuation wires 32.

Referring now to FIG. 2b , there is shown a plan view an exemplaryembodiment the metallic reinforcing layer 53 of the flexible shaft 50.For purposes of illustration and not limitation, as embodied herein,tubular wall of the metallic member preferably has one or moreperforations 54 defined therein. The perforations 54 generally areoriented circumferentially about tubular wall of the metallic member.Preferably, in accordance with this exemplary embodiment of theinvention, the perforations 54 are disposed circumferentially about wallin pairs so as to define hinge points 55 therebetween. As depicted, eachperforation 54 subtends an angle of less than 180 degrees of thecircumference of cylindrical wall. However, a single perforationsubtending an angle greater than 180 degrees is also within the scope ofthe invention. Perforations 54 can be formed by laser discharge,milling, etching or any other suitable techniques. Collectively,perforations 54 are preferably sized and shaped, and spaced from oneanother to modify the flexural characteristics of the flexible member 50in a predetermined manner without altering the compressibility of theflexible shaft 50. For example, alternating pairs of perforations 54 canbe rotated with respect to each other by a predetermined angle, such as90 degrees. In this manner, it is possible to provide for enhancedflexure of the flexible shaft 50 in two directions that aresubstantially perpendicular to one another. Similarly, the longitudinalspacing between perforations can be varied to provide for varyingrigidity along the length of the flexible shaft 50. Likewise, thecircumferential placement of perforations 54 can be varied to impartdesired bending characteristics to the flexible shaft 50. Additionalspacings between perforations along the length of the flexible shaft 50may be implemented, if desired, to vary flexural characteristicsgradually, or in a step like fashion.

There are many ways in which the perforations 54 can be shaped andarranged in accordance with the invention. In one embodiment, theperforations can be varied in size and/or in longitudinal spacing tocreate regions of greater or lesser axial flexibility. Furthermore,alternating pairs of perforations 54 need not be alternated merely byrotating them 90 degrees. Any pattern of rotation to create a desiredbending characteristic can be achieved. Moreover, the perforations donot need to be circumferentially aligned slit shapes. For example, andin accordance with an alternate embodiment of the invention theperforations 54 may include longitudinal components, such as an I-shape.In accordance with this aspect of the invention, perforations 54 includea circumferential component and a longitudinal component. A variety ofother shapes and arrangements are possible for perforations 54. Forexample, the perforations can be ellipsoidal in shape or could take theform of a curved slot or be formed such that the perforations 54 formarticulating joints having male and female components that are pivotallycoupled.

In yet another alternative embodiment, the flexible shaft 50 may beformed of one or more coil assemblies. It is contemplated that two coilassemblies can be utilized to form the flexible shaft 50 or at least onelayer of a multiple layer flexible shaft as described above. Wherein aninner coil would be wound having a specific pitch and the outer coilwould be wound having a specific pitch, wherein the coils' pitchesdefine flexible properties of the flexible shaft 50. The flexibility ofthe flexible shaft 50 may be further tuned or adjusted by varying thethickness of the material from which the coil assemblies are constructedof.

The flexible shaft 50 may further include a pre-formed curve disposedadjacent to the proximal end of the foot housing 60 as shown in FIG. 11.The pre-formed curve in the flexible shaft 50 aligns the foot housing 60nearly perpendicular to the PFO within the septum as shown in FIGS. 6and 7 and will be described in greater detail below with regard to themethods according to the present invention. By aligning the devicenearly perpendicular to the PFO, tissue capture on the superior side ofthe PFO is greatly enhanced since the needle is nearly perpendicular orperpendicular to the superior side of the PFO. The angle of thepre-formed curved section is formed so that the device fits within theanatomy of the right atrium and across the PFO naturally. It shall beunderstood that the angle of the device may be adjusted prior toinsertion of the device by bending, heat forming or similar methods. Itis further contemplated that a steering device or mechanism may beintegrated into the flexible shaft 50, wherein an adjusting membercoupled to the steering device disposed on the handle portion 20 may beutilized to adjust the angle of the pre-formed curved portion of theflexible shaft. The pre-formed curve section may have an angle betweenabout 0 and 180 degrees, more preferably between about 10 and 80 degreesand most preferably between about 30 and 60 degrees. It is furthercontemplated that an introducer sheath/catheter may be utilized toposition the device 10 in accordance with present invention, wherein theintroducer would have a pre-formed curve disposed therein and beutilized to locate the device 10 within the PFO as described above.

Referring now to FIG. 3 there is shown a cross-sectional view of theflexible shaft 50 taken along line 3-3 of FIG. 1. The cross-sectionshown in FIG. 3 is at a location along the length of the shaft proximalto the cross-section of FIG. 2. At the location shown in FIG. 3, theneedle actuation shaft 41 is shown, as well as the suture storage lumen80 and the foot actuation wires 32, each of which will be described ingreater detail below.

Referring now to FIG. 4, there is shown the needle assembly 45, whereinthe needle assembly includes a needle actuation handle 40, a needleactuation shaft 41 and at least one needle 42, and more preferably atleast two needles 42. As shown in FIG. 4, the needle actuation shaft 41is a generally elongated member having proximal 43 and distal 47 ends,wherein the proximal end 43 is coupled to the distal end of the needleactuation handle and the distal end 47 is configured to fixedly receivethe proximal end of the needles 42. The two needles 42 may be force fitinto the distal end 47 of the needle actuation shaft 41. Alternatively,a needle-retaining feature, such as a proximally extending barb, may beprovided on the proximal end of the needle 42, wherein the distal end 47of the needle actuation shaft may be overmolded, thereby capturing theneedles in a fixed position. Still further, it is contemplated that theneedles may be attached to the needle actuation shaft utilizing otherattachment methods such as glues, welding, friction/interference fit, orthrough the use of locking features.

The needle actuation shaft 41 is preferably constructed having goodflexibility while exhibiting good compressive strength. The needleactuation shaft 41 may be constructed in a similar manner to theflexible shaft 50, wherein the needle actuation shaft may be constructedof multiple layers or as a composite member. For example, the needleactuation shaft may include a metallic core such as that shown in FIG.2b , wherein the metallic core is covered with a plastic covering.Alternatively, the needle actuation shaft may be formed from a unitarymember such as a plastic or metallic tube or rod. Suitable metallicmaterials include stainless steel, nitinol, high tensile stainless steelor similar metals.

In a preferred embodiment and as shown in FIG. 4, one needle 42preferably has a length greater than the other needle. The difference inlengths of the needles is so that the tips of the needles will engagethe respective needle receptacles 66 in the foot 65, when the foot 65 ispivoted to a deployed position that is at a non-perpendicular angle tothe axis of the foot housing 65 as shown in FIG. 12. It is furthercontemplated that at least one of the needles may be constructed havinga detachable needle tip 49, wherein the detachable needle tip isconfigured to disengage from the shaft of the needle 42 when thedetachable needle tip 49 is received within the needle receptacle 66 ofthe foot 65 as will be described in greater detail below with regard tothe methods according to the present invention. Additionally, one end ofthe suture 34 is configured to be attached to the detachable needle tip49, therefore, when the detachable needle tip 49 is detached from theneedle 42, the suture 34 remains with the detached needle tip 49.

Referring now to FIG. 5, there is shown an enlarged view of a portion ofthe foot housing 60, wherein the foot 65 is illustrated in a deployedconfiguration. In order to advance the foot from the deliveryconfiguration to a deployed configuration, the foot actuation handle 30pivotally disposed on the handle portion 20 is moved from a firstposition generally flush with the handle portion to a second positiondisposed at an angle to the handle portion 20. The actuation of foothandle 30 slides one of the foot actuation wires 32 proximally, pullingfoot 65 from a parked position shown in FIG. 1, to the deployed positionillustrated in FIG. 5. Once deployed, a first end 65 a and a second end65 b of foot 65 extend laterally from the foot housing 60 at an anglerelative to the foot housing. The distance between the first end 65 a ofthe foot and the foot housing 60 is greater than the distance betweenthe second end 65 b of the foot and the foot housing 60, wherein thepivot point of the foot 65 is not disposed about a symmetrical axis ofthe foot 65. The first end 65 a of the foot is longer than the secondside 65 b of the foot to help prevent the foot from being pulled backthrough the atrial septum during the procedure. An exemplary ratio ofrelative lengths of the two sides of the foot may be 1.5 to 1.0.

To return the foot 65 to the delivery configuration from the deployedconfiguration, the foot actuation handle 30 is pivoted towards the firstposition, which causes the foot actuation wire 32 connected to thesecond side of the foot 65 to be pulled in the proximal direction topivot the foot 65 back to the delivery configuration, wherein the foot65 is substantially aligned with the foot housing 60. As shown in FIG.5, a bearing 33 is positioned proximal to the pivot point 68 of the foot65 to provide a surface against which the foot actuation wires 32 slide.The bearing 33 is positioned such that the foot actuation wires 32 arerouted over the bearings 33 to change the direction of the pulling forceagainst the foot 65. In particular, the wire 32 attached to the inferiorside 65 b of the foot 65 is routed so that the pull force is transmittedto the foot at an angle that is roughly perpendicular to the lever armof the foot 65 with respect to the pivot point 68 of the foot. This isto insure that the foot 65 may be fully returned to the deliveryconfiguration wherein the foot 65 is substantially aligned with the foothousing 60.

The pre-formed curve in the foot housing 60 of the device 10 as shown inFIG. 1 enables the device 10 to fit within the patient's anatomy bydisturbing the PFO superior septum flap less due to the pre-formed curveportion while at the same time increasing tissue capture by favoringcapture on the superior side, and minimizing needle free flight length.The pre-formed curve sections may be manufactured according to theintended use of the device 10. For example, a different curve may berequired if the device is to be used in the right atria vs. a devicethat is intended to be utilized in the left atria. Further still, thedevice may be manufactured wherein multiple foot housing geometries maybe provided, such that during a procedure a surgeon may choose anappropriate foot housing geometry based upon the patient's anatomy.

The foot 65 further includes needle receptacles 66 adjacent the ends 65a and 65 b of the foot, wherein the receptacles are configured to retaina cuff 67. The two cuffs 67 are coupled together with a flexiblefilament (not shown), wherein the flexible filament is configured to bedisposed along the length of the foot. The flexible filament maycomprise a length of suture, a length of wire, Teflon, nitinol, orsimilar materials. Additionally, the cufth are configured to receive theends of the needles 42. The suture 34 in accordance with the presentinvention may comprise a continuous filament with one end attached tothe detachable needle tip and the other end attached to the otherneedle.

In the deployed position, the angle of the foot relative to the guideportion is approximately less than 90 degrees, more preferably less than80 degrees and most preferably about 51 degrees. The deployed angle maybe selected to be any angle that provides optimal apposition of the footagainst the tissue surface that is to be sutured, because the atrialseptum, including the septum primum and the septum secundum, will varyin physical orientation, size and thickness from patient to patient.

The foot housing 60 in accordance with the present invention may beconstructed of stainless steel for enhanced visualization underfluoroscope. Alternatively, the foot housing may be constructed of anon-radiopaque material wherein radiopaque markers may be provided onthe foot housing 60 or the foot 65 to further enhance radiopacity of thedevice during the suturing procedure. As descried above, in addition toretaining the pivotable foot 65, the foot housing may further includeneedle guide paths (not shown) that direct the needles 42 away from theaxis of the foot housing 65 and toward the needle receptacles 66 and thecuffs 67 disposed within the foot 65. Alternatively, radiopaque markersmay be disposed along the length of the flexible shaft 50 or along thelength of the distal sheath 70.

In another embodiment (not shown), the foot 65 may include multiplepairs of needle receptacles 66. Such an embodiment may be desirable whenmore than one suture loop will be used to suture the PFO. The needlereceptacles 66 may be oriented in a side-by-side fashion with respect tothe length of the foot 65, or in a longitudinal orientation on the foot.As such, additional pairs of needles 42 and suture 34 will also beprovided in addition to the multiple needle receptacles 66.

The various embodiments of the suturing device 10 in accordance with thepresent invention may include any of a variety of types of suture, suchas braided or monofilament. The suture material may be absorbable ornonabsorbable and may be made of polyester, polypropylene, polyglycolicacid, nylon, silk or any of a variety of suture materials known in theart. Suture material coated with antibiotics or other antimicrobialagents may also be provided with the suturing devices of the presentinvention.

An exemplary suture material is TEVDEK II®, a braided polyester suturematerial that is impregnated with PTFE and manufactured by GenzymeBiosurgery of Cambridge, Massachusetts. An exemplary monofilament suturematerial is DEKLENE II®, a polypropylene suture material alsomanufactured by Genzyme Biosurgery. Another exemplary monofilamentsuture material is nylon monofilament, also manufactured by GenzymeBiosurgery.

Monofilament suture material tends to be stiffer relative to braidedsuture material. As such, forming a bight of suture for the purpose ofproviding a pre-tied knot is more difficult with monofilament suturethan with the more flexible braided suture. The monofilament suturematerial will tend to straighten itself out after being looped to form abight as previously described. Therefore, in order to provide a bight ofmonofilament suture that is releasably disposed on the shaft of thedevice without unraveling the loops forming the bight are heated to setthe bight. The heating of the bight of monofilament suture to set thebight is performed after the suture has undergone any manufacturingprocedures that may include drawing, annealing or any other procedurethat employs heat to manufacture the suture material.

Further still, the device 10 in accordance with the present inventionmay be utilized with modified suture, wherein the suture may be modifiedto provide retention in tissue. One example of such a suture can be seenwith regard to FIG. 6a , as shown in FIG. 6a , the suture 134 includes afirst end 133 and a second end 135, wherein a knot 136 is formed in thesuture adjacent the second end 135. In use, the suture is deliveredacross an opening, wherein the first end of the suture 133 is utilizedto tighten the suture 134 and close the opening. By applying a force tothe first end 133 of the suture, the knot 136 is advanced along thelength of the suture. A feature 137 disposed at the second end of thesuture 135 prevents the second end of the suture 134 from being drawnthrough the knot 136, wherein the applied force causes the knot 136 totighten. The knot 136 may be formed such as a clinch knot, sliding knot,bowline, half-hitch or similar knot styles.

Referring now to FIG. 6b , there is shown an alternative embodiment of asuture that may be utilized with the device 10 in accordance with thepresent invention. As shown in FIG. 6a , the suture 234 may have alocking element 236 disposed on a second end 235 of the suture, whereina plurality of beads 237 are formed along the length of the suture 234as shown in FIG. 6b . In use, the suture 234 is disposed across anopening, wherein the first end 233 of the suture is passed through thelocking element 236 disposed on the second end 235 of the suture 234.The beads 237 formed along the length of the suture pass through thelocking element 236, wherein the locking element 236 is designed to onlyallow the beads 237 to pass through in one direction, therebyeffectively closing the opening. The beads 237 may be heat formed,mechanically formed, or integrally formed along the length of the suture234 or may be formed as knots. It is further contemplated that lockingelement 236 may be embodied in the form of a knot similar to thosedescribed above with regard to FIG. 6 a.

It shall be understood that the sutures described above and shown hereinare examples of suitable sutures that may be utilized with the deviceand methods of the present invention and should not be consideredlimiting in any manner. Further still, the ends of the suture may bedistinguished from each other by changing the color of one end (e.g.with dye), providing an attachment on one end (e.g. shrink wrap tubing,a bead, etc.) or with the suture itself (e.g. tying a knot in one end).Alternatively, one end of the suture may be colored through a dyeprocess.

It is further contemplated that a sealing member may be utilized incombination with the device and methods according to the presentinvention. Examples of exemplary sealing members can be seen withreference to FIGS. 6c and 6d , where there is shown two sealing memberswhich may be utilized with the methods according to the presentinvention as will be described in greater detail below.

Referring now to FIGS. 6c and 6d there is shown an exemplary embodimentsealing members which may be additionally be included for use with thedevices and methods in accordance with the present invention. Referringnow to FIG. 6c , there is shown a sealing member 250 includes a firstend 253 and a second end 255 wherein the first end includes at least onesuture aperture 252 and more preferably at least two suture apertures.The suture apertures may be constructed having a locking feature,wherein the suture is passed through the suture apertures 252, whereinas the sealing member 250 can then be only advanced in one directionalong the length of the suture, thereby tensioning and locking thesuture disposed across the opening. The sealing member 250 may beconstructed of a biocompatible mesh material such as PTFE, Nylon,nitinol or similar materials, wherein the sealing member is configuredto be disposed on between the patient's tissue forming the PFO and theknot or suture clip device. The sealing member may be configured to bean expandable member, or other types of sealing devices. For example,the sealing member may further include a gel, foam, glue, or similarsealing products, or the sealing member may be constructed of abioabsorbable material such that the sealing member would be eventuallyabsorbed. Further still, the sealing member may be integrally formedwith the suture clip device, wherein both the sealing member and thesuture clip device can be deployed in a single action.

Referring now to FIG. 6d there is shown a cross-sectional view of analternative embodiment of a sealing member 260 in accordance with thepresent invention. As shown in FIG. 6d , the sealing member 260 includesa base member 261 and a locking member 263, wherein the base member andthe locking member are preferably constructed of biocompatiblematerials. The base member may be constructed in a manner such that thebase member has a first diameter and a second diameter, wherein thefirst diameter may be a delivery diameter and the second diameter isgreater than the first diameter. For example, the base member may beconstructed having a metal support structure formed of nitinol and amembrane covering, wherein the nitinol metal frame expands upondelivery. The base member further includes at least one lumen formedtherein, the lumen configured to receive at least one suturetherethrough. The membrane covering the frame of the base member mayfurther include a gel, foam, glue, or similar sealing products, or thebase member may be constructed of a bioabsorbable material such that thebase member would be eventually absorbed. The locking member 260 isconfigured to receive at least one suture and fixedly retain the suturein relation to the locking member.

Referring now to FIG. 7, there is shown a partial plan view of analternative embodiment of the closure device 10 in accordance with thepresent invention. As shown in FIG. 7, the device 10′ includes a suturebight 101 detachably attached to the device adjacent the foot housing60. The bight of suture 101 is disposed within an opening formed in thetubular member 50, wherein the bight 101 is detachably attached to theflexible shaft 50. In use, the foot 65 is deployed, the loop of suture34 serves to pull the bight of suture 101 down a rail portion of thesuture during deployment. It should be noted that it would be desirableto be able to distinguish the ends of the suture 34 as described above,such that during deployment the correct end of the suture is pulled bythe operator to advance the bight of suture 101 to form a knot. Shouldthe non-rail end be pulled, the knot may be prematurely tightened beforeit is advance to its deployed position at the wall of the vessel.

Referring now to FIG. 8, there is shown an exemplary embodiment of adistal end of an alternative embodiment of a foot housing and footmember in accordance with the present invention, wherein like numbershave been used to denote components described above but not shown. Asdescribed above, the suturing device 300 shown in FIG. 8 includes ahandle member 20 (not shown) including a foot actuation lever 30 (notshown) and a needle actuation handle 40 (not shown) and an elongatedflexible shaft 50, a foot housing 360 and a distal sheath 370. As shownin FIG. 8, the device 300 includes a first foot 365 a and a second foot365 b as well as first and second needles 342 a and 342 b. As shown inFIG. 8, the first foot 365 a pivots about first pivot point 368 a andthe second foot 365 b pivots about second pivot point 368 b, wherein thefirst and second pivot points are offset from one another. Furtherstill, the first and second foot 365 a and 365 b may be operatedindependently of one another or simultaneously. As shown the first foot365 a is configured to engage a proximal surface of the septum secundumand the second foot 365 b is configured to engage a distal surface ofthe septum primum. After the foot members 365 a and 365 b have beendeployed, the needles 342 a and 324 b are advanced, thereby penetratingthe septum primum and septum secundum respectively. After the needleshave been advanced through the tissue, the tips of the needles engagethe foot members. As shown in FIG. 9 pusher member 343 disposed within alumen of one of the or each of the needles 342 a and 342 b is activatedto expel suture 334 having a toggle 336 attached to an end thereof fromthe lumen formed in the needle 342. After the suture(s) have beendeployed, the needles and foot members can be retracted, wherein thesuturing device 300 may then be retracted from the patient, therebyleaving a suture member 334 disposed across the PFO. The toggle 336 maybe fixedly attached to one end of the suture and be slidably attached tothe other end of the suture, wherein the slidable toggle 336 isconfigured to slide in only one direction in a similar manner to thesuture locking system previously described. In use, the slidable togglemay be advanced along the length of the suture, wherein the togglegrasps and retains the suture. An exemplary embodiment of the suturepath formed by the suturing device 300 can be seen with reference toFIG. 10.

Methods of Use

A procedure for closing a PFO using a suturing device in accordance withthe principles of the invention is now described. Subcutaneous access tothe right common femoral vein is gained via a puncture in the groin areaof a patient. A trans-septal sheath or similar sheath with a dilator isadvanced through the puncture, into the femoral vein and further throughthe inferior vena cava. The sheath may be further advanced into theright atrium of the heart. In one embodiment, the sheath defines aslight curvature at its distal end to match the anatomy of the patient.After placing the sheath in a desired location the dilator is removedfrom the sheath, thereby leaving the sheath within the patient'svasculature.

A guidewire is advanced through the sheath and further into the rightatrium. The guidewire is advanced through the PFO, through the leftatrium, and may be further advanced into the pulmonary vein. The distalend portion of the guidewire can be positioned in the pulmonary vein toremain there for the duration of the procedure. Alternatively, theguidewire may be advanced through the PFO without the use of a sheath.

The suturing device in accordance with the present invention may then beadvanced over the guidewire. The device is advanced into the heart suchthat the foot is positioned past the atrial septum as shown in FIG. 9.Proper placement of the device may be determined through the use ofimaging technologies such as X-ray or fluoroscopy, wherein theradiopaque foot housing can be visualized relative to a patient'sanatomy. Further still, it is contemplated that the device may include apressure sensor disposed adjacent to the foot or foot housing, wherein achange in pressure or a pressure fluctuation may be used to determinelocation of the device within the patient's anatomy. In yet anotherembodiment, it is contemplated that the suture device in accordance withthe present invention may include a bleedback port or other visiblemarking device, which may be used to determine placement of the device.After the device has been properly placed within the atrium of thepatient and the foot housing is advanced a sufficient length into thepatient's atrium, the foot 65 may be deployed from the foot housing 60as shown in FIG. 10. To deploy the foot, the user applies a force to thelever 30, thereby applying a force to the actuation wires 32. Once thefoot 65 is deployed, the suture device is pulled back slightly such thatthe foot contacts the atrial septum. By pulling slightly back on thedevice the atrial septum is pulled up against the foot 65 of the device10, thereby increasing the likelihood of needle penetration and tissuecapture. Additionally, by pulling back on the device the physician isprovided with tactile feedback ensuring that the foot 65 has beenproperly deployed and engaged with the septum primum and secundum. Theneedle actuation handle 40 is then pressed to advance the needles 42through the tissue and into the cuffs 67 disposed in the receptacles 66formed in the foot 65.

In one embodiment, one of the needle tips carrying one end of the suturewill detach from the needle shaft and be received by a needle cuff. Thesecond needle will be received by a second needle cuff, wherein theneedle and needle cuff will remain attached to one another, wherein eachof the needle cuffs area interconnected to one another with a flexiblefilament or a short length of flexible material such as that describedabove. The needle actuation handle 40 is then pulled out of the housingof the device to remove the needles and pull the length of sutureproximally, thereby positioning a loop of suture across the PFO.

The foot 65 is then advanced from the deployed configuration to adelivery configuration and the device may then be removed from thepatient.

A knot may be tied, or advanced if the suturing device includes a bightor pre-formed knot which is deployed during the needle advancement step.It is further contemplated that a suture lock or clip may be used tosecure the ends of the suture and close the opening in the atrium inplace of forming a knot. Further still, a sealing member such as thatshown in FIGS. 6c and 6d may be disposed along the length of the sutureprior to the formation of a knot or deployment of a suture-lockingdevice. The tails of the suture may then be cut from the knot. In yetanother alternative embodiment, the tails of the suture may be severedby applying a pre-determine amount of force to the tails of the suture,wherein the tails of the suture will sever due to the applied force. Theseverance of the suture tails in this embodiment may be further enhancedwith the addition of a feature or features formed along the length ofthe suture thereby forming a weakened zone or region.

While the exemplary embodiments have been described in some detail forclarity of understanding, a wide variety of modifications, adaptations,and changes will be apparent to those of skill in the art. Hence, thescope of the present invention is limited solely by the appended claims.

1.-18. (canceled)
 19. A method for closing a septal defect, the methodcomprising: following positioning a first extendable member againsttissue adjacent the septal defect, advancing a suture material throughthe tissue; following positioning a second extendable member againstother tissue adjacent the septal defect and on an opposite side of thetissue adjacent the septal defect from the first extendable member,advancing other suture material through the other tissue; and securingthe suture material and the other suture material to close the septaldefect.
 20. The method of claim 19, wherein the first extendable membercarries a portion of the suture material.
 21. The method of claim 19,wherein the second extendable member carries a portion of the suturematerial.
 22. The method of claim 19, wherein the first extendablemember pivots relative to an elongate member.
 23. The method of claim19, wherein the second extendable member pivots relative to an elongatemember.
 24. The method of claim 19, wherein advancing the suturematerial through the tissue comprises drawing the suture proximallythrough the tissue.
 25. A method for closing a septal defect, the methodcomprising: positioning a first extendable member against a septumsecundum, a portion of a septum primum and a portion of a tunnel betweenthe septum secundum and the septum primum being disposed between thefirst extendable member and a portion of the septum primum; advancing asuture material through the septum secundum; and securing the suturematerial to close the septal defect.
 26. The method of claim 25, whereinadvancing the suture material through the septum secundum comprisesadvancing the suture material proximally through the suture material.27. The method of claim 25, further comprising positioning a secondextendable member against the septum primum.
 28. The method of claim 27,further comprising advancing a toggle through the septum primum.
 29. Themethod of claim 28, further comprising securing the suture with thetoggle.
 30. A method for closing a septal defect, the method comprising:positioning a first extendable foot against either of a septum primum ora septum secundum adjacent the septal defect; positioning a secondextendable foot against the other of the septum primum or the septumsecundum at a location positioning the septum primum between the firstextendable foot and the second extendable foot; advancing a suturematerial through the septum primum; and securing the suture material toclose the septal defect.
 31. The method for closing the septal defect ofclaim 30, wherein positioning the first extendable foot comprisespositioning the first extendable foot against a proximal surface of theseptum secundum.
 32. The method for closing the septal defect of claim30, wherein securing the suture comprises advancing a slidable togglealong the suture.
 33. The method for closing the septal defect of claim30, wherein the suture comprises a fixed toggle and a slidable toggle.34. The method for closing the septal defect of claim 30, furthercomprising advancing a portion of an elongate member supporting thefirst extendable foot through a tunnel between the septum secundum andthe septum primum.
 35. The method for closing the septal defect of claim34, wherein a bight of the suture material is supported by the elongatemember.
 36. The method for closing the septal defect of claim 30,wherein positioning the first extendable foot comprises moving anactuation wire, connected to the first extendable foot, proximally.